The longer answer: A comparative look at the beliefs and practices of Christian, Jewish and Muslim congregations across the United States confirms much that was already suspected: the majority of Protestant churches are rural; Jews participate more readily in interfaith activities; and African-American churches offer a wide range of community services, such as tutoring, substance abuse and employment counseling.

But the conclusions drawn in the new booklet, “Meet Your Neighbors: Interfaith FACTs,” reveals much that is new too. For example, the study, conducted by researchers at Hartford Seminary’s Hartford Institute for Religion Research, shows that Muslims place more emphasis on abstaining from both alcohol and premarital sex than any of the other faith groups.

The booklet, which consists of data gathered in 1999 and 2000 as part of the “Faith Communities Today” project, is not intended to provide positive or negative evaluations of the different faiths. Instead, it is supposed to flesh out similarities and differences between the traditions and increase sensitivity to the nation’s diverse religious landscape.

The data collected here — mostly in charts and graphs — gives a picture of where each of the seven faith families is located and when it was founded. For example, the booklet shows that Jewish, African-American and Muslim congregations are predominantly urban, while the majority of white Protestant congregations are rural. For purposes of the study, the U.S. religious scene is split up into seven faith families: Old-line Protestants, Evangelical Protestants, Roman Catholics, Orthodox Christians, African American Protestants, Reform and Conservative Jews, and Muslims.

Among the study’s more intriguing comparisons are the similarities between different religious groups. Muslims, Orthodox Christians, and Roman Catholics, for example, place a high emphasis on family devotions, fasting and holy day observances. Muslims and Evangelical Protestants encourage abstinence from premarital sex. The study shows that the majority of congregations, regardless of tradition, are involved in community service, with food pantries and soup kitchens the most common service offered. The information gathered for this booklet was culled from questionnaires with 14,301 pastors, rabbis, imams and lay leaders who were asked what practices their congregations emphasized most.

The study suggests minority faiths are growing fastest— perhaps because their numbers were relatively small to begin with. Seventy-two percent of Muslim respondents said their mosques had grown by 5 percent or more since1995. And 68 percent of Jews said their synagogues and temples had grown by 5 percent or more. In contrast, the majority of Old-line Protestants reported their churches did not grow, and both Old-line and Evangelical Protestants reported that 19 percent of respondents said they had lost 5 percent or more of their members during the final half of the 1990s.

The study also shows that religious groups reach out differently to new members. Liturgical churches, such as Roman Catholic and Orthodox Christian congregations, have the hardest time designing special services intended to attract non members, while Jews and Protestants are more flexible in creating worship services specifically geared at potential newcomers.

Finally, when it comes to leadership, Reform and Conservative Jewish congregations have the highest percentage of full-time clergy — 88 percent. Mosques, by contrast, reported the lowest percentage of full-time clergy — 45 percent. (This may have something to do with the different role of clergy. Islam does not have an ordained clergy, and the imam is considered a prayer leader.) Protestant churches have the highest numbers of active lay members — more than 30 percent — compared with fewer than 10 percent for Muslims and Roman Catholics. One reason may be that Protestants have more church activities outside of worship.

Carl S. Dudley and David A. Roozen, the authors of the study, said they hoped the comparisons would allow congregations to find similarities in faith practices, even if the doctrines remain different. And they suggest, in learning about others religious groups may ultimately arrive at a keener understanding of themselves.